That is an access hole to manually close your sunroof if it has an issue. Honda's with sunroofs come with a hex tool that fits in there and is like a crank, or at least they used to.
Make sure you guys take the seats out wear gloves eye protection sweatshirt and sweatpants and mask do not do it in a garage unless you wet the floor and get a dust collector trust me I didn’t do anything I listed above now my car is covered in fiberglass that you cant see only feel and this shit is itchy and irritating
Ok an update on mine I jus removed it if its getting hard to take it off u just have to slide it to the front side and remove ur seats mines was kinda hard to take it off the car
the head liner you are showing is a lot more work because of the sun roof, right? Cars without a sunroof, you don't have to worry about all those brackets in the middle that you are showing at around 12:00 minutes into the video?